垂体瘤的CT和MRI增强

Enhanced CT and MRI in the Diagnosis of Pituitary Adenomas

目的：分析垂体瘤的ＣＴ和ＭＲＩ增强表现，探讨增强后ＣＴ和ＭＲＩ对诊断垂体瘤的价值。材料和方法：对手术和病理证实的２４２例垂体瘤，回顾性分析ＣＴ和ＭＲＩ增强前后表现。结果：２４２例中微腺瘤（≤１０ｍｍ）８１例，大腺瘤（＞１０ｍｍ）１６１例。微腺瘤直接征象为垂体内的ＣＴ低密度或ＭＲＩ（Ｔ１ＷＩ）低信号。增强后ＣＴ和ＭＲＩ显著提高低密度或低信号的显示率（Ｐ＜０．０１）。大腺瘤增强后扫描肿瘤均有不同程度的强化。ＣＴ和ＭＲＩ增强对于显示肿瘤的部位、大小、范围、鞍旁结构如海绵窦和颈内动脉的受侵情况以及显示残存正常垂体均有很高的价值。介绍了一种新的ＭＲＩ垂体瘤分级方法－ＳＩＰＡＰ分级系统。结论：ＣＴ和ＭＲＩ增强对垂体瘤的定位、定性、定量和定级诊断均具有至关重要的作用。

Purpose:To investigate the values of enhanced CT and enhanced MRI in the diagnosis of pituitary adenomas.Materials and Methods:Pre-and post-contrast CT and MRI of 242 cases of pituitary adenomas,proven surgically and pathologically,were retrospectively reviewed.Results:81 of 242 cases were microadenomas(≤10mm in diameter).They appeared in low density on CT or hypointensity in MRI as the direct signs.The detectivity of low density or hypointensity was significantly increased after administration of CT or MRI contrast media.161 of 242 cases were macroadenomas(>10mm in diameter)showing various contrast in the post enhanced CT or MRI.No enhancement could be seen in the areas of hemorrhage,capsulation,necrosis and calcification.Contrast enhancement of CT and MRI were capable of delineating size,location,extent of the tumours and the remaining intact pituitary tissue.They were also helpful in detection of lesions at parasellar structures especially cavernous sinus and internal carotid artery.In addition,SIPAP grading system for pituitary adenomas was recommended.Conclusion:Enhanced CT and enhanced MRI play very important roles in localization,qualitation,quantitation and grading of pituitary adenomas.